Portugal has not given the world a huge quantity of composers of renown, especially if its mini-golden age before 1700 is discounted. It was not really until the twentieth century that the country's reputation properly picked up, chiefly thanks to the trinity made up of Luís de Freitas Branco, Joly Braga Santos and Fernando Lopes-Graça. This disc of chamber music from the latter follows on from two orchestral volumes released by Naxos in 2012 and 2013, both of which were met with widespread plaudits (8.572892 - review, 8.572817 - review).

This latest discographic entry is welcome in more ways than one: though hardly a stranger to recordings, much of Lopes-Graça's music, like that of Freitas Branco and Braga Santos, still remains unrecorded – and thus unappreciated. Of the programme on offer here, opp. 105, 188 and 218 are, according to the booklet, premiere recordings – nearly a third in terms of minutes. All the other works except Esponsais actually appeared first on CD on a double disc (only 88 minutes in total however) from the Portuguese multi-genre CNM label, re-released in 2006 to mark the centenary of the composer's birth. However, the engineering quality of brother and sister team Vasco and Grazi Barbosa's re-mastered 1972 recordings remind the listener what Portuguese audiophiles have had to put up with over the years.

In musical terms, Lopes-Graça (pronounced roughly 'lopzh-grahssa') may profitably be thought of as a Portuguese Bartók: he does a similar line in rhythmic spikiness, ethereal lyricism and folk-inflected chromaticism. Probably most striking is the way he experiments ceaselessly with rhythms, textures and timbres, but never in an avant-gardist way – his canvases always have background washes coloured by the music of his Iberian and European forebears. Bartók was not known for his sense of humour, and to judge by the cover photo, Lopes-Graça might be thought to 'follow' him in this regard too. Yet, though much of his music is the product of hard times – he was no stranger to imprisonment or the threat of it for his political dissent – and consequently relatively dark-edged, he is less sardonic than he might have been. There are many dance-like rhythms and at times, as in the final Galope of op.33, there is a kind of wry wit in evidence.

Ranging from five to ten minutes in length, none of these works, it should be said, is of first-rank significance as such, yet the fact that each bears an opus number reflects the importance that Lopes-Graça himself attached to them. They are definitely not fripperies or fillers. Every piece has its own distinctive character, twisting, driving, chasséing, distilling and soaring in a multitude of arresting ways.

Each work also makes almost relentless virtuosic demands of both pianist and especially violinist. These roles are excellently filled by Bruno Monteiro and João Paulo Santos, two of Portugal's leading chamber musicians, presenting the first item from a three-disc Naxos deal. They have recorded together a number of times recently: Robert and Clara Schumann for Centaur (review), Saint-Saëns/Strauss for CNM (review) and, with the Lopes-Graça Quartet, Chausson, again for Centaur (review). All have rightly been well received. Their teamwork is virtually telepathic, but individually too they bring maximal intelligence to these works, blending gravitas and lightness, passion and discipline, the Lusitanian and the cosmopolitan.

Sound quality is first-rate – one of the better recordings to have come out of Portugal. The church at Cartuxa gives the notes plenty of air, but not too much of it. The booklet contains detailed notes by Ana Carvalho, informative and cogent, and well translated into English by Monteiro himself.

A sign of the times, in a sense, this recording is only available from Naxos as a download or streamed, but the physical CD can still be ordered from a number of online Portuguese sources, including Fnac and Monteiro's own website. However obtained, it is hard to imagine anyone being anything but delighted with their purchase.